Folder taper machine



July 16, 1963 A. F.sH1E1 Ds 3,097,575

' FOLDER TAPER MACHINE Filed Aug. 21. 1961 e sheets-sheet 1 July 16, 1963 A. F. SHIELDS FOLDER 'PAPER MACHINE Filed Aug. 21, '1961 6 ShQebs-Sheet 2 INVENTOR. 4L 5527' F. Dy/Izar `Iuly 16, 1963 A. F. sHlE'Lps FOLDER TAPER MACHINE e sheets-sheet s Filed Aug. 2l, 1961` INVENTOR. Lafer f? .IW/zow July 16, 1963 -A. F. sHlELDs FOLDER TAPER MACHINE 6 Sheets-Sheet 4 Filed Aug. 21. 1961 July 16, 1963 A. F. SHIELDS 3,097,575

FOLDER TAPER MACHINE Filed Aug. 21, r19m e sheets-sheet 5 A. F. SHIELDS FOLDER TAPER MACHINE July 16, 1963 6 Sheets-Sheet 6 F1166 Aug. 21. 1961 Wai/ufff United States Patent O 3,097,575 FOLDER TAPER MACHINE Albert F. Shields, Forest Hills, ANQY.`,"'assign or to S & S Corrugated Paper Machinery Company, Inc., Brooklyn, N.Y`., a corporation of Newok Filed Aug.`21, 1961, Ser. No. 132,816

7 Claims. (Cl- Q3..49)

The present invention relates to improvements in the blank stopping means and blank straightening means for a -folding machine of the type generally sliownin my prior Patent No. 2,622,493 wherein large size corrugated board or other paper blanks are passed from a stack through various folding Aelements and delivered to a mechanism which `applies tape to the folded blanks.

In the making of cartons it is necessary first to crease and slot the blanks in order to properly prepare them for the folding operation. The machine illustrated in my aforesaid Patent 2,622,493 accomplishes folding b yimeans of folding plates operable upon the blanks while the `blanks are stopped. The machine is adjustable to Yaccommodate Ia wide size range of boxes.

In adjusting the machine for a different size box it is necessary to move the blank stopping means at the folding station. Thus, the blank stopping means includes stops movably mounted on longitudinally extending members. The construction of the machine is such that the mechanisrn feeding the blanks to the folding station includes continuously'operated roller means which drives each blank against the stops.

For the folding of short blanks it was necessary to adjust the stops to a more rearward position than is necessary when long blanks are being folded. The stop supportin-g bar is mounted at the rear end thereof so as to enable an actuating mechanism to pivot the bar and thereby raise the st ops into thefeedf path of the unfolded blanks. After lthe blanks are folded the actuating mechanism lowers the stops permitting the blanks to be removed 4from the folding station by a pusher.

The :arrangement hereinbefore Voutlined had a number of ydisadvantages when the machine is operated Iat high speed, For example, of necessity, the spaces between large blanks in lthe machine is smaller than the spaces between -small blanks. Because 4of this with large blanks being folded the stop supporting bar begins to rise before the folded blanks have been moved clear of the stops. This brings the stops intowengagement with the blank being removed often pausing marring ofthese blanks.

Also, mounting of the stop supporting barl at Ione of its ends at a pivotal support means that the stops when adjusted for la small blank will not be movable to as high a position Ias when adjusted for a large blank. lf the stops were made very high to assure. foolproof operation in the case of short blanks this would `reguire a large movement of the stop supporting bars with attendant high amplitude vibrations. Even with a compromise Ipivot setting the long bars often break at their pivotal securement point.` The bars cannot be effectively reinforced to prevent breakage since the added weight required to aceomplish this purpose would impede the `high `speed operating of the machine.

The device of the instant invention overcomes the difficulties outlined above by providing a stop supporting bar which is mounted so that it will remain substantially parallel to the horizon-tal as the stops are raised and lowered. This is accomplished by means of a `spo-called parallel operating linkage. With this arrangement .the stops will rise to the same height when the machineis adjusted for operation on either long or short blanks. Beeause of this, the travel of the `stop supporting bars may be maintainedat a minimum so -that'rthe raising of the 'bars may ICC be postponed until such time as long blanks have Ybeen entirely removed from the folding station. In addition the parallel operating linkage supports the stop supporting bar Vat both ,ends rather Ithan in the cantilever fashion of the prior art so that breakage is minimized.

In the machine of my aforesaid Patent 2,622,493, the blanks are moved `at high speed into the folding station. Their movements are halted abruptly by engagement with the stops. If precautions were not taken thisl i would cause rebounding of the blanks so that they ywould not be in proper position for engagement by the folding bars. In my laforesaid Patent No. 2,622,493 rebounding is prevented by wed'ging the blanks between the guide bars and sloped portions of the stops. This hasproven to `be less than satisfactory because of the short braking distance involved. Y

To alleviate this condition the instant invention includes means for gradually decelerating the blanks as they approached the stops and also to prevent rebound from-the steps. This means comprises guide bars of relatively large surface area along which the blanks move while they are at the folding station. The guide bars `are coristructed to support the blanks during folding inV a manner suc-h that double breaks -will not occur. Downward pressure exerted by `the folding guide bars forces the blanks against the extensive surface ofthe supporting guide. Ibar vso that decelerating action takes place over a relatively long distance.

In the device of my aforesaid Patent 2,622,493 a straightening means in the form of rollers which engage the folded edges are provided forward of the folding vstation. The folded blank is wed-ged between these rollers prior to the application of tape. While these rollers are effective to bring badly misaligned panels in to reasonably good alignment, for some purposes the alignment has proven not to be within tolerances.

In order to further improve straightening the instant invention provides a member which engages the folded blank just prior to the application of the tape. Engagement is at the forward -ends of lthe blanks in the region where the folded over panels will have tape applied thereto. The member in question is constructed of material having a relatively high coefficient of friction and is mounted so as to force the blanks back against the pusher which removes the folded blanks from the folding station and delivers them to the taping head.

Accordingly, a primary Aob-ject of this invention is Vto provide a novel construction for a box folding machine.

Another object is to provide a folding machine having novel stop operating means. i

Still another object is to provide :a folding machine having novel means for decelerating blanks prior to their engagement with thefstops at the folding station.

`A yfurther object is to provide a folding machine having novel means to support the blanks during the folding operation.-

A still further object is to provide a folder taper having novel means :for aligning the panels of the blanks just prior to the application `of tape.

These objects, as well as further objects of this invention shall beome aparent after reading the following description of the accompanying drawings in which:

FIGURE 1 is a plan view of my novel improved folding machine.

FIGURE 2 is a side view of the machine of FIGURE l.

FIGURE 3 is a side view partly in cross seetion corresponding to the side View of FIGURE I2 taken along lines 3-3 of FIGURE `l.

FIGURE 4 is a cross section view showing the manner in which blanks enter the region of the'ffolding plates. FIGURE 5 is an enlarged Ifragmentary portion of FIG- URE 2 illustrating the parallel operating mechanism for the stop supporting bars.

FIGURE 6 is an enlarged cross section taken through line 6-6 of FIGURE 5 looking in the direction of arrows 6 6.

FIGURE 6A is a plan view of the stop illustrated in FIGURE 6.

FIGURE 7 is a partially sectioned plan View of the cam operating means for the mechanism of FIGURE 5.

FIGURE 8 is a side elevation of the mechanism of FIGURE 7 looking in the direction of arrows 8-8.

FIGURE 9 is a side elevation of the cam and cam follower of FIGURE 7.

FIGURE l is a plan view of the elements illustrated in FIGURE 9 looking in the direction of arrows 10AM).

FIGURE lll is a side elevation of the straightening means at the taping station.

FIGURE 12 is a front elevation of the straightening 'means of FIGURE lil looking in the direction of arrows FIGURE 13 is an exploded perspective of the blank decelerating means and blank stopping means.

Now referring to the figures and more particularly to FIGURES 1, 2 and 3. My novel folding machine, generally indicated by reference numeral 20, comprises a stacking section including bed 21 whereon a stack of blan'ks 22 is placed. Stack -22 is placed between side gauges 26, 27 with the trailing and leading edges of the stack 22 in engagement with the rear and front gauges 24, 25, respectively. As is Well known to the art, front gauges 25 are adjusted vertically so that they present a passage just high enough to permit one of the blanks in stack 22 to pass therethrough while holding back the remainder of the stack.

A blank pushed by feed slat 33 between the upper and lower feed rolls 35 and 36, respectively, passes below lfront gauges 25 over bar 31 and idling roller 32. Feed rolls 35 and 36 engage the blank and carry it `forward to the upper and lower feed rolls 37 and 38. Feed roll 33 on the underside of the blank comprises a plurality of short collars extending across the width of the machine whereas the upper feed roll 32, actually consists of two rollers 37a and 37b (FIGURE 1) which are adjustable by means of rotatable screws 29 so as to engage only the unfolded panel of the blank; that is, feed rollers 37a, 37b are adjusted so that they are just within the fold lines as defined by folding bars 39 and 40.

The blanks are then fed by feed rolls 37 and 38 be tween the upper and lower feed rolls 41 and 42 with upper feed roll 41 actually consisting of two feed rolls 41a and 41b transversely aligned fwith feed rolls 37a and 37b and simultaneously adjustable therewith. Cornpression spring 48 is positioned to urge lower feed roll 42 upward toward feed roll 41 and in a similar manner rolls 35 and 38 are also biased toward their cooperating rolls 36 and 37, respectively.

The blank is then carried under folding guide bars 39 and 40 and over feed rolls 53 which are biased upwardly by tension spring 57 and are opposed by an upper pair of rollers (not shown) mounted on folding guide bracket 16. Feed rolls 53 are rotatably mounted at 54 to one end of arm y55 whose other end is pivoted at 56. Rolls 53 engage the blank and carry it fonward until the front edge of the blank engages stops 101 mounted on stop bars `102. The lforward progress of the blank is thus arrested.

While the blank is in this position with its forward edge against the two stops 101, the score lines about which folding is to take place are in register with the outer edges of folding guide bars 39 and 40. Folding plates 60, held on respective cross arms 61, are driven around to fold the side panels toward one another. Each of the cross arms 611 which supports -its individual folding plate 60 is driven by link I62 connected to crank l63 which in .4 turn is driven by the mechanism within the folding gear boxes 64.

After the folding of the side panels, plates 60 are withdrawn. Stops 1011 are lowered in a manner to be hereinafter explained and slat 90 mounted across chains 91 and equipped with extended tabs to hold the panels down moves into engagement rwith the rear of the folded blank and moves the blank underneath hold-down strip 92 which is adjustably supported by bracket 93 on cross bar 95. Hold-down strip 92 is adjusted so that it extends just in lfront of stops 101. The front end of strip 92 is curved upwardly so that panels which tend to spring up after being folded will be guided down again and their longitudinally extending edges brought to abutting position preparatory to having tape applied thereto. As soon as slat 90 on chains 91 engages and moves the blank forward hold-down strip 92 presses down on the blank between the panels and prevents the folded blank from opening.

The blank is then carried forward between the limiting rolls and 71 which, as shown in FIGURE v3, loosely control the position of the delivery end of folding bars 39 and 40. Since the folding guide bars 39, 40 are supported from the mountings for front guides 25 of the stacking section and since the free or delivery ends of the folding guide bars 39, 40 are a substantial distance from these supports the forward ends of the bars may be moved through a small distance even though the rear ends of bars 3-9, 40 are held fixed. Rollers 70, 71 above and below each of the folding bars 39 and 40 limit the upward and downward movement of the free ends of folding bars 39 and y40 so that they will not be flexed excessively. These rollers 70, 71 also control the blank and hold it in a somewhat central position so that the folded edges of the blank will be properly engaged by straightening rollers positioned -in two longitudinal extending rows so as to engage the folded edges of the blanks. The spacing between rows of aligned straightening rollers 75 is adjusted so as to form an opening which is slightly less than the width of the folded blank. Slat forces the blank between the rows of rollers 95 with the edges of the blank guided in the annular grooves of roller 75. Since the rows of rollers 75 are spaced slightly closer together than the width of the folded blank the crease or fold is adjusted and folded vertically. The movement of slat 90 'which maintains the body of the folded blank nonmal to its direction of travel holds the blank at the correct angle with respect to rolls 75 so that in a properly folded blank the crease is adjusted regularly on each side.

Where the score line was initially incorrect or where the panel was folded improperly the lines are adjusted and straightened so that recreasing rolls 76 may then recrease or press the folds properly. After recreasing by roller 76 the blank is moved fonward to taping station indicated generally as 180 whereat a longitudinal strip of tape is applied to bridge the space between the confronting free edges of the folded over panels.

Folding machine `20 includes a variable speed D.C. motor and sprocket means (not shown) which drives shaft 153 carrying sprocket 154. Sprocket 154 provides power to pull slat carrying chains 91 which are held by idler sprockets on shaft 156. Shaft 153 also holds another sprocket which drives sprocket 163 thus driving lower delivery shaft 141 and upper delivery shaft 140 as well as taper cam shaft 166.

-One end of shaft 153 holds bevel gear l170 which drives bevel gear 171 keyed to shaft 172. As will be fully explained hereinafter, shaft 172 through couplings 173 and 175 drives the input shaft `174 of transmission 199 which shaft 207.. and thus turns the spur gear 208 which is also keyied to sha-ft 207. The teeth of :gear `208are in mesh with the' teeth of gears 2091-211; andthus drive gears 220-222lwithgear 1222 driving gear 1223. Itcan bem seen that by means of this gearing thefeed rolls 35-38 and 41'are alldriven. Also rolls .35 yand 38are pivotally held on the centers of gears 222 and20i9, respective-ly, so Vthat these feed rolls when spring biased will adjust themselves to any thickness Vof blank.

Gear 230 on shaft 2001 drives gear 23'1 which holds Ibevel gear 232. Bevel gear 232 `drives bevel gear 233 on kicker drive shaft 234. Asis Wellknown to the art, the rotary motion of shaft` 234acting through suitable linkages drives kicker bar 33 which carries spring kickers 33a.

Machine 20 is adjusted forthe folding of different lwidth boxes through the simultaneous rotation of leadscrews 29. and 29a by means of adjusting motor 300, as is fully explained in my aforesaidPatent 2,622,493, with the rotation of screws 129 laterally adjusting carriages 301 and the'rotation of leadscrews 29a being effective to laterally adjust folding plates 60 as well as thefdriving mechanisms therefor.

One important aspect of this invention is the improved means for the mounting of stop bars 102and means for imparting motion thereto. lThis feature is most clearly illustrated in FIGURES 5`-10. Referring now Ato these figures, each of the stop bars `1,02` is provided with longitudinallyrspaced brackets 401, andA 402 pivotallymounted at y403A and 404, respectively, to one end of cranks 405, 406 respectively. The central portion of crank 405 is mountedto stationary support shaft `407 while the othery end ofA crank 405 is pivotally mounted to i408A to one end of tie bar 409.

Keys 4104 and 411, key rock shaft 412 to crank 406 at the central portion thereof. The other end of crank 406 is pivotally mounted` at 413 to the other end of tie bar 409. Tension spring 41-4 is mounted to screw 4135 which is carried by member 416 secured by screws 417 to tie bar 409. The other end ofspring 414 is provided with a` hooked end extending through eye 419 of threaded member 420. The threaded portion of member 420 extendsthrough an aperture stationary portion 421 of the machine frame with nuts 422, 423 mounted on opposite sides of portion 421 providing means for adjusting the loading of spring 414.

It is to be noted that tie bar I409 :extends substantially parallel to stop bars 102 and that cranks I405 and 406 are of substantially identical` construction so that upon the pivoting of rock shafty412 pivot points 403 and 404 will undergo identical motions. IBecause of this, all points onstop bars 102` will move to the same extent in the `same direction. Thus, it is seen that any new position assumed by stop bars '102 will be parallel to the previous position which, as illustrated in FIGURE 5, is substantially horizontal. Because of this, whether stop '1 is mounted to the left of stop bar :102 with respect to FIGURE 5 for operation on short boxes or to the right on stop bar 102 with respect to FIGURE Sfor operation on long boxes, the vertical movement whichV stops 101 undergo is the same. Because of this even when long blanks are being operated upon stop 101, now positioned at the right of stop bar i102, moves throu-gh a small vertical distance so that it is notnecessary to begin to raise stop 102 into the feed path of the next unfolded blank until the prior folded blank has cleared the folding station.

Rockingrnotion is Yimparted to rock shaft412 by transmission 199. Transmission 199 comprisesL drive shaft 174 which extends parallel to the longitudinal axis of machine 20 through the side walls of transmission housing 350. Bevel gear 351 keyed to shaft 174 drives bevel gear 352 keyed to stub shaft 353. Key 35,4 mounts cam 425 to bevel gear 352 for rotation -in unison thereiwth. Follower wheel 355 mountedl to one end of follower arm 356 engages the periphery of cam 425. Arm 356, at the other end thereof, is secured by pin 357 to rock shaft 412 6 which extends `parallel to stub shaft 353Nthrough thevrear wall 358 of`housing 35,0.

Stub shaft 353extends through coverplate-359 atthe front of housing 350 with the portion o fjstub shaft 353extending externally of housing 350vcarrying hand wheel 360.. -Cover vplate 359 is maintained in sealing relationship over housing aperture 3 61v by means of 'clamping'levers 362, 363 which are pivotally mounted to pins 364, 365, respectively. Pins 364, 365 are mounted to the front of4 housing350 extending forward thereof With washers 366 interposed `between clamping levers 362, 363 and'housing 35.0,. to appropriately positioned`1evers`362 and 363), for engagement with the front surface of cover plate 359V.`

`With levers 3,62`and 363 in the dotted line positions ofFIGURE 8 hand wheel 360 may be moved forward` to disengage bevel gear 352 from Ibevel gear 351, so that cam'425; may have the positions thereof adjusted with the rise 4260i cam 425 being brought into thejposition of FIGURE 9 at the appropriate time. It is noted that bearing 37,1 of4 stubjshaft 352 comprises an inner racer 3.72'whieh is laterally movable with respect to outer race 37.3 so as to permit axial movement of stub shaft 353.

The relative angular positions of bevel gears 351V and 352 is setso thatV stops 101 will bein raisedl position just,y prior to the arrival of anunfolded blank at the folding station. Spring 414 biases rock shaft 412f in a counterclockwise direction with respect to FIGURES 5 and 9 so 'that `cam follower 355 is urged against the periphery of -cam 425. As is clearly seen in FIGURE 9, cam 425 is so shaped that the ydwell encompasses most of a cycle and that there is -a steep rise and fall to and from rise 426. With follower 355 in engagement with rise 426, rock shaft 412 is rotated to its most clockwise position of FIG- URE l0 andin this position stops 101 are raised.

Each of the stop supporting bars 102 is an elongated member of L-shaped cross-section with the vertical leg having longitudinally spaced apertures 45,0 which receives pin 451 for maintaining stop 101 in longitudinal position along stopsupporting bar 102, By withdrawing pin 451 to the right with respect to FIGURE 6 st op101 may be moved longitudinally along bar 102 to the position required for the length of the -boxrbeing worked upon. Y

In somewhat greater detail stop 101 is mounted to inverted modified U-shaped block 601 at the forward end thereof Iby means of three screws 602.. Block 601 extends over stop bar 102 and is xed against transverse movement by means of member 603 mounted by screws 604 internally of one of the legs of block 601. 'Ihe complementary bevelled edges 605 and 606 of member 603 and stop bar 102, respectively, perform the transverse locking function while still permitting longitudinal movement of block 601 along stop bar 102.

lOne end of` pin 451 is provided with reduced end 611 Leaf spring 612 aiixed to block 601 by screws 613 enof reduced area which is sized to t within apertures 450. Leaf spring 612 afiixed to block 601 by screws 613 engages the other end of pin 451 urging it toward stop bar 102.

Release pin 615 is disposed within bore 616 of block 601. One end of release pin 615 carries manually engageable pin 616 while the other end of release pin 615 is provided with a flattened portion 613 having an inclined cut out 6169. The flattened portion of release pin 615 extends through a slot in pin 451 bounded in part by surfaces 621 and 622.

The latter is inclined in the same direction as surface 619 and cooperates therewith to enable end 611 of pin451 to be withdrawn from the stop bar aperture 450 when the position of stop 101 is to be changed. That is, by manually moving release pin 615 to the left with respect to FIG- URE 6A inclined surface 622 moves to the left moving pin 451 -against the bias of spring 612-to move end 6111 out o f aperture 450. Thereafter, stop 101 is moved to the d esired position along stop bar 102. Release pin 615 is moved to the right permitting end 611 of nin 451 to enter another stop bar aperture 451. Movement of release pin 615 to the right with respect to FIGURE 6A is limited by the fact that spring 612 urges pin 451 into the inclined cut away 619.

Each stop supporting bar 102 is positioned below a folding support bar 455 which is secured to housing 302 of folding box 64 and movable therewith transversely of machine 20. As blanks are delivered to the folding station by feed rolls 41, 42 these blanks are supported by the horizontal leg 456 of folding support bar 455. It is noted that element 455 is an elongated member of L-shaped cross-section and that leg 456 thereof provides a relatively extensive bearing surface which cooperates with folding guide bar 40 to define passage 457 which is very low in height being only slightly greater than the thickness of the blank material.

Because of the relatively extensive surface area of leg 456 the blank in moving forward of feed rollers 41, 42 is greatly decelerated so that it will not be travelled at an excessive speed upon engagement with stop 101. Inclined surface 650 immediately to the rear of stop 101 provides additional deceleration lfor the blank prior to its engagement with stop 101. In addition, the extensive surface area of leg 456 provides support for the blank adjacent to fold 456 while side section 461 is being folded over. In the absence of support at this point there is a tendency `for double folds to form. That is, one fold would take place along the score line where it is intended (as indicated at 460) and another fold would take place at the left edge of `folding .guide bar 460.

While the two rows of aligned rollers 75 which engage the folded longitudinally extending edges 460 to straighten the blanks as they leave the folding station, it has been found that for some applications the straightening achieved by rollers 75 is not sufficient. In order to improve the straightening operating squaring element 500 is positioned in the path of the blanks as they are being moved forward by slat 90. Element 500` is positioned immediately rearward of the taping head 502 and engages the leading edge of each blank at the free ends 462 of the foldedover panels 461.

Stationary element S is constructed of material such as hard rubber, having a relatively high co-eicient of friction, is mounted to the hinge support comprising plates 504, 505 pivoted to pin 506. Bolts 507 secure hinge plate 505 to frame member 508. Fastening means comprising screws 510 and nuts 511 in conjunction with backing plate 512 secure squaring elemen-t 500 to hinge plate 504. Torsion springs 515 are mounted to pivot member 506 at opposite ends of hinge plates 504, 505. Anchor pin 518 iixedly secures one end of spring 515 to pivot member 506 While the other end of spring 515 is clamped between member 510 and hinge plate 504 by screw means 521.

Springs 515 are so arranged that as a folded blank moves forward (in the direction of arrow A FIG. ll) the leading edge of the folded blank engages squaring element 500 which applies a force against the leading edges of the folded-over portions 461 tending to force these edges into alignment with the leading edge of the unfolded portion of blank 460. Springs 515 urge element 500 in a counterclockwise direction about pivot 506 to the position shown in FIGURE ll. As the blank moves forward element 500 is moved about the feed path, that is, clockwise with respect to pivot 506. After the folded blanks move forward of squaring element 500 la tape strip which, as is well known to the art, overlaps the free edges 462 of the folded-over panels 461 is applied at taping station 80.

Thus, this invention provides an improved construction for a folder taper with the specific improvements residing in the provision of a parallel operating mechanism for stops 101, the relatively large bearing surface of folding support bars 455, .the simple arrangement for adjusting the position of cam 425 and the provision of squaring element 500.

Although I have here described preferred embodiments of my novel invention, many varia-tions and modifications will now tbe apparent to those skilled in the art, and I therefore prefer to be limited not by the specific disclosure herein but only by the appending claims.

I claim:

l. `In a folding machine for forming at, collapsed tubular box blanks from scored flat sheets having a pair of longitudinally extending side sections defined by score lines and foldable about said score lines into said collapsed itubular box blanks; said machine comprising a folding station including stop means; means for moving said blanks successively forward against said stop means; means at said folding station for folding over said side sections along said score lines; conveyor means for moving folded blanks forward out of said folding station; longitudinally extending bar means upon which said stop means is adjnstably mounted; an operating mechanism for raising said stop means into the path of unfolded blanks and for lowering said stop means out of the path of folded blanks longitudinally extending folding guide bars at said folding station; longitudinally extending supporting guide bars positioned below said folding guide bars with a space therebetween so proportioned that blanks passing therebetween will have a gradually decelerating force applied thereto prior to engagement with said stop means; said supporting guide bars including ia relatively extensive upper surface upon which blanks are supported as they move against said stop means.

2. In a folding machine for forming flat, collapsed tubular box blanks from scored at sheets having a pair lof longitudinally extending side sections defined by score lines and foldable about ysaid score lines into said collapsed tubular box blanks; said machine comprising a folding station including stop means; means for moving said blanks successively forward against said stop` means; means iat said folding station for folding over said side sections along said score lines; conveyor means for moving folded blanks forward out of said folding station; longitudinally extending bar means upon which said stop means is adjustably mounted; an operating mechanism for raising said stop means into the path of unfolded blanks and for lowering said stop means out of the path of folded blanks; forward of folding station, straightening means engageable with said blanks as they are being moved by said conveyor means; said straightening means including a member positioned to engage the leading edges of the folded side sections to properly align these sections; a pivotal suppont for the last recited member, said pivotal support being positioned above the path taken by the folded blanks whereby the last recited member is deflectable upward in a first direction to permit passage of said blanks along said path, and biasing means urging said last recited member in a second direction toward said path and returning said last recited member to a position to engage the leading edge of a succeeding blank after the trailing edge of a preceding blank has moved forward of said last recited member.

3. The machine of claim 2 in which the straightening means also includes rollers aligned in two rows with the rows positioned so that the rollers thereof engage the longitudinally extending edges of the folded blanks as the blanks are being moved by said conveyor means.

4. The machine of claim 2 in which the last recited member is comprised of material having a relatively high coefficient of friction.

5. In a folding machine for forming flat, collapsed tubular box blanks from scored flat sheets having a pair of longitudinally extending side sections defined by score lines and foldable about said score lines into said collapsed tubular box blanks; said machine comprising a folding station including stop means; means for moving said blanks successively forward `against said stop means;

Imeans at said foldingA station for folding over said side sections along said score lines; conveyor means for moving folded blanks forward out of said folding station; longitudinally extending bar means upon which said stop means is adjustably mounted; and a parallel operating mechanism for rtaising said stop means into the path of unfolded blanks and for lowering said stop means out of the path of folded blanks; said parallel operating mechanism comprising first and second crank means mounted to said Alongitudinally extending bar means near opposite ends thereof and a connecting ibar means extending between said crank means and positioned parallel to said longitudinally extending bar means; a rock bar to which one of said crank means are keyed; cam follower means keyed to said rock bar; a cam for imparting a rocking motion to said follower means which is transmitted through said rock bar and said parallel operating mechanism to said longitudinally extending bar means; a main drive shaft for said machine and a iirst gear keyed to said drive shaft; a second gear in driving engagement with said lirst gear and a stub shaft to which both said cam and said second gear lare keyed; means mounting said stub shaft for limited axial movement to permit disengagement of said gear and permit adjustment of said cam.

6. In a folding machine for forming hat, collapsed tubular box blanks from scored flat sheets having a pair of lon-gitudinally extending side sections defined by score lines and foldable about said score lines into said co1- lapsed tubular box blanks; said machine comprising a folding station including stop means; means for moving said blanks successively forward against said stop` means; means at said folding station for folding over said side 4sections along said score lines; conveyor means for moving folded blanks forward out of said folding station; longitudinally extending bar means upon which said stop means is adjustably mounted; an operating mechanism for nais-ing said stop means into the path of unfolded blanks and for lowering said stop means out of the path of folded blanks; forward of said folding station, a taping station through which said blanks are moved by said conveyor means; said taping station including means for applying a tape strip` which overlaps confronting edges of said folded side sections; and straightening means including a member positioned rearward of said last recited means and positioned to engage the leading edges of the folded side sections prior to the application of tape to properly align these sections; a pivotal support for the last recited member, said pivotal support being positioned above the path taken by the folded blanks whereby the last recited member is deectable upward in a lirst direction to permit pas-sage of said blanks along said path, and biasing means urging said last recited member in a second direction toward said path :and returning said last recited member to a position to engage the leading edge of a succeeding blank aiter the trailing edge of a preceding blank has moved forward of said last recited member.

7. The machine of claim 6 in which the last recited member is comprised of material having a relatively high coeiiicient of friction.

References Cited in the file of this patent UNITED STATES PATENTS 2,442,839 Carlson .Tune 8, 1948 2,664,035 Roselius Dec. 29, 1953 2,898,821 Shields Aug. 11, 1959 2,915,950 La Bombard Dec. 8, 1959 3,018,099 Seel Jan. 23, 1962 

1. IN A FOLDING MACHINE FOR FORMING FLAT, COLLAPSED TUBULAR BOX BLANKS FROM SCORED FLAT SHEETS HAVING A PAIR OF LONGITUDINALLY EXTENDING SIDE SECTIONS DEFINED BY SCORE LINES AND FOLDABLE ABOUT SAID SCORE LINES INTO SAID COLLAPSED TUBULAR BOX BLANKS; SAID MACHINE COMPRISING A FOLDING STATION INCLUDING STOP MEANS; MEANS FOR MOVING SAID BLANKS SUCCESSIVELY FORWARD AGAINST SAID STOP MEANS; MEANS AT SAID FOLDING STATION FOR FOLDING OVER SAID SIDE SECTIONS ALONG SAID SCORE LINES; CONVEYOR MEANS FOR MOVING FOLDED BLANKS FORWARD OUT OF SAID FOLDING STATION; LONGITUDINALLY EXTENDING BAR MEANS UPON WHICH SAID STOP MEANS IS ADJUSTABLY MOUNTED; AN OPENING MECHANISM FOR RAISING SAID STOP MEANS INTO THE PATH OF UNFOLDED BLANKS AND FOR LOWERING SAID STOP MEANS OUT OF THE PATH OF FOLDED BLANKS LONGITUDINALLY EXTENDING FOLDING GUIDE BARS AT SAID FOLDING STATION; LONGITUDINALLY EXTENDING SUPPORTING GUIDE BARS POSITIONED BELOW SAID FOLDING GUIDE BARS WITH A SPACE THEREBETWEEN SO PROPORTIONED THAT BLANKS PASSING THEREBETWEEN WILL HAVE A GRADUALLY DECELERATING FORCE APPLIED THERETO PRIOR TO ENGAGEMENT WITH SAID STOP MEANS; SAID SUPPORTING GUIDE BARS INCLUDING A RELATIVELY EXTENSIVE UPPER SURFACE UPON WHICH BLANKS ARE SUPPORTED AS THEY MOVE AGAINST SAID STOP MEANS. 